The present invention relates to a method of decreasing the content of impurities in alkoxysilanes.
In alkoxysilanes used as industrial materials in the technical field of semiconductors, it has been found that a small amount of halides such as organic halide compounds present therein as impurities often corrode semiconductor substrates and cause problems in semiconductor materials.
As a method of reducing the content of impurities in alkoxysilanes, for example, JP-A-63-238091 discloses a method of using a metal alcoholate in an amount more than the chemical equivalent amount of the chloride compound to be contained in an alkoxysilane as an impurity. (The term "JP-A" as used herein means an "unexamined published Japanese patent application".) In this method, however, removal of organic halide compounds is difficult. On the other hand, JP-A-63-77887 describes a method of purifying an organic silicon compound by bringing the compound into contact with an organic magnesium compound. However, industrial preparation of organic magnesium compounds used in this method is difficult. Additionally, when the method is applied to purification of alkoxysilanes, the alkoxy group reacts with the organic residue of the organic magnesium compound and thereby lowers the yield of the alkoxysilane product. Thus, this method has various problems.